/****************************************************************************
 *
 * Copyright 2016 Samsung Electronics All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 ****************************************************************************/

/*
 *  VIA PadLock support functions
 *
 *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
 *  SPDX-License-Identifier: Apache-2.0
 *
 *  Licensed under the Apache License, Version 2.0 (the "License"); you may
 *  not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *  This file is part of mbed TLS (https://tls.mbed.org)
 */
/*
 *  This implementation is based on the VIA PadLock Programming Guide:
 *
 *  http://www.via.com.tw/en/downloads/whitepapers/initiatives/padlock/
 *  programming_guide.pdf
 */

#include "tls/config.h"

#if defined(MBEDTLS_PADLOCK_C)

#include "tls/padlock.h"

#include <string.h>

#ifndef asm
#define asm __asm
#endif

#if defined(MBEDTLS_HAVE_X86)

/*
 * PadLock detection routine
 */
int mbedtls_padlock_has_support(int feature)
{
	static int flags = -1;
	int ebx = 0, edx = 0;

	if (flags == -1) {
		asm("movl  %%ebx, %0           \n\t" "movl  $0xC0000000, %%eax  \n\t" "cpuid                     \n\t" "cmpl  $0xC0000001, %%eax  \n\t" "movl  $0, %%edx           \n\t" "jb    unsupported         \n\t" "movl  $0xC0000001, %%eax  \n\t" "cpuid                     \n\t" "unsupported:              \n\t" "movl  %%edx, %1           \n\t" "movl  %2, %%ebx           \n\t" : "=m"(ebx), "=m"(edx)
			:			"m"(ebx)
			:			"eax", "ecx", "edx");

		flags = edx;
	}

	return (flags & feature);
}

/*
 * PadLock AES-ECB block en(de)cryption
 */
int mbedtls_padlock_xcryptecb(mbedtls_aes_context *ctx, int mode, const unsigned char input[16], unsigned char output[16])
{
	int ebx = 0;
	uint32_t *rk;
	uint32_t *blk;
	uint32_t *ctrl;
	unsigned char buf[256];

	rk = ctx->rk;
	blk = MBEDTLS_PADLOCK_ALIGN16(buf);
	memcpy(blk, input, 16);

	ctrl = blk + 4;
	*ctrl = 0x80 | ctx->nr | ((ctx->nr + (mode ^ 1) - 10) << 9);

	asm("pushfl                        \n\t" "popfl                         \n\t" "movl    %%ebx, %0             \n\t" "movl    $1, %%ecx             \n\t" "movl    %2, %%edx             \n\t" "movl    %3, %%ebx             \n\t" "movl    %4, %%esi             \n\t" "movl    %4, %%edi             \n\t" ".byte  0xf3,0x0f,0xa7,0xc8    \n\t" "movl    %1, %%ebx             \n\t" : "=m"(ebx)
		:		"m"(ebx), "m"(ctrl), "m"(rk), "m"(blk)
		:		"memory", "ecx", "edx", "esi", "edi");

	memcpy(output, blk, 16);

	return (0);
}

/*
 * PadLock AES-CBC buffer en(de)cryption
 */
int mbedtls_padlock_xcryptcbc(mbedtls_aes_context *ctx, int mode, size_t length, unsigned char iv[16], const unsigned char *input, unsigned char *output)
{
	int ebx = 0;
	size_t count;
	uint32_t *rk;
	uint32_t *iw;
	uint32_t *ctrl;
	unsigned char buf[256];

	if (((long)input & 15) != 0 || ((long)output & 15) != 0) {
		return (MBEDTLS_ERR_PADLOCK_DATA_MISALIGNED);
	}

	rk = ctx->rk;
	iw = MBEDTLS_PADLOCK_ALIGN16(buf);
	memcpy(iw, iv, 16);

	ctrl = iw + 4;
	*ctrl = 0x80 | ctx->nr | ((ctx->nr + (mode ^ 1) - 10) << 9);

	count = (length + 15) >> 4;

	asm("pushfl                        \n\t" "popfl                         \n\t" "movl    %%ebx, %0             \n\t" "movl    %2, %%ecx             \n\t" "movl    %3, %%edx             \n\t" "movl    %4, %%ebx             \n\t" "movl    %5, %%esi             \n\t" "movl    %6, %%edi             \n\t" "movl    %7, %%eax             \n\t" ".byte  0xf3,0x0f,0xa7,0xd0    \n\t" "movl    %1, %%ebx             \n\t" : "=m"(ebx)
		:		"m"(ebx), "m"(count), "m"(ctrl), "m"(rk), "m"(input), "m"(output), "m"(iw)
		:		"memory", "eax", "ecx", "edx", "esi", "edi");

	memcpy(iv, iw, 16);

	return (0);
}

#endif							/* MBEDTLS_HAVE_X86 */

#endif							/* MBEDTLS_PADLOCK_C */
